Sessions Abstracts

Tuesday, 26 June 2012, 13:30 - 17:35

Results on Behaviour, Acceptance and Usage (Longitudinal Functions)

A main activity of the evaluation in euroFOT is the analysis of the user related aspects. This evaluation consists of several activities. The evaluation is based on the analysis of objective data, collected from the FOT vehicles and subjective data, collected by means of time based questionnaires. By applying a set of indicators the impact of the tested function on the driver related aspects is assessed. Based on hypotheses (derived from the research questions of the project), a comparison between the baseline phase (tested functions not available) and the treatment phase (tested function available) can be established. This allows the assessment of the impact of the tested function.

 

The following aspects are considered for the assessment of the driver related aspects:

  • Driver behavior
  • Acceptance
  • Usability
  • Workload
  • Trust

Within this session the results of the longitudinal functions tested in euroFOT will be presented. These functions are:

  • Adaptive Cruise Control (ACC)
  • Speed Regulator System (SRS)
  • Forward Collision Warning (FCW)

 

Results on Behaviour, Acceptance and Usage (Lateral and Special Functions)

A main activity of the evaluation in euroFOT is the analysis of user related aspects in relation to the evaluated functions. The evaluation is based on a combination of objective data from the FOT vehicles and subjective data, collected by means of a series of time based questionnaires.

A number of hypotheses on how the presence of each function might influence various aspects of driver behaviour, acceptance, workload, usability and trust were evaluated.

Within this session, results for the lateral and general functions tested in euroFOT are presented. These functions are:

 

  • Lane Departure Warning (LDW)
  • Impairment Warning (IW)
  • Blind Spot Information System (BLIS)
  • Fuel Efficiency Advisor (FEA)
  • SafeHMI (Navigation System)

 

Impact and Cost Benefit Analysis

The analysis of impacts from the use of ADAS on safety, traffic efficiency and the environment is a key task in euroFOT. Surrogate measures are investigated to derive estimates for the potential reduction in the number of accidents and injuries. Given sufficient evidence from hypothesis testing, these estimations are achieved by comparing events and performance indicators from the FOT with real world data from in-depth accident analysis and national accident statistics. Beyond that, fuel savings and time savings are quantified assuming a traffic system wide implementation. The benefits for traffic and environment are derived by taking an “indirect modelling route” via traffic simulation, based on aggregated FOT results.

The cost-benefit analysis in euroFOT is based on welfare economics and will provide decision makers and stakeholders with relevant estimates on the effect of the functions tested on society’s welfare by comparing monetary benefits and costs to society. For this purpose, it amends the FOT results with data regarding market conditions and economic resources needed to implement the systems. Given the European scope of euroFOT, the results obtained allow an estimation of potential benefits and costs for EU-27. 

 

 

Wednesday, 27 June 2012, 09:00 - 16:30

Hypotheses and Experimental Design

Developing hypotheses and the experimental design are rather theoretical and dry research topics. Nevertheless they are vital for any experiment and a Field Operational Test (FOT) is an experiment that is very large and takes place in a complex environment. As in any other experiment, the objective is to test whether the experimental manipulation (in euroFOT, e.g. LDW or FCW) has an effect on the driving behaviour. The question is how driving behaviour changes compared to driving without a system.

The fact that an FOT takes place under noisy measurement conditions (real world traffic) increases the need for a good preparation of the experiment. A priori well defined hypotheses need to be formulated. These hypotheses describe the relevant conditions, what needs to be measured, and what the effect is expected to be. They also should cover both positive and negative effects. These hypotheses are then used as the basis for determining the performance indicators (e.g. average speed and time headway) and variables that may influence these performance indicators (situational variables such as weather conditions).

The hypotheses are also used to determine the experimental method that still needs to be developed even though data is collected under ‘chaotic’ conditions. The experimental method describes how long different measurement periods have to be, what kind of drivers should participate, at what times questionnaires should be administered etc. This session will cover the important and often underestimated preparations of an FOT and will also describe some of the lessons learned on performing an FOT.

Data Collection and Management

Proper data collection and management are essential for the success of any FOT and naturalistic driving study. To achieve that, different requirements – ranging from technical and operational issues, time and budget constraints, as well as analysis plans – have to be considered: sometimes, compromises have to be made. This session will describe the challenges faced by the euroFOT partners in data collection and management. It will further highlight and motivate the solutions finally chosen, and it will point out the key lessons learned.

FOT Execution

The FOT operation is the central element of a field operational test. It has to deal with the challenging issues of the recruitment, the setup, the driving and the handover of the data collected during the driving phase. These tasks are even more complicated in the context of the project considering the heterogenic test environment such as the multitude of functions and their different combinations, the different kinds of test cars, the extensive geographical distribution of the test etc. The scope of the session is to show how the different project partners were able to solve the issues and what lessons these solutions provided for the wider FOT community to improve the available operational methodology.

 

Evaluation Methodology

This session presents the methodology of the data analysis. The goal is to assess the societal and individual impacts of the Advanced Driver Assistance Systems (ADAS) that are tested in the euroFOT project. Data analysis methods are described in four different presentations.

The user-related aspects that are assessed are driver behaviour, driver workload, driver acceptance, trust, function usage, and exposure. In this assessment both objective data and subjective data are used. The assessment involves hypothesis testing.


The purpose of the safety impact analysis is to assess the extent to which the functions being evaluated in euroFOT can be expected to alter the current crash populations at EU level in terms of accidents, injuries and fatalities. The traffic efficiency aspects that are assessed are travel time and accident-related congestion. The analysis determines the impact of the euroFOT functions on travel time losses and accident-related congestion at EU level. For the environmental assessment, fuel consumption and CO2 emissions are assessed, again at EU level. For both, the efficiency and environmental impact assessment, two approaches are used: a linear approach and a modelling approach. The linear approach uses FOT data directly and effects are scaled up to EU level via situational variables. The modelling approach uses FOT data as input for traffic simulations and environmental models, in order to model the interaction between equipped and non-equipped vehicles at higher penetration rates than those in the FOT.


The approach for the socio-economic cost-benefit analysis is presented. The results of the impact assessment will be scaled up to EU level to serve as input for the socio-economic cost-benefit analysis. Scaling up of traffic efficiency and environmental effects is based on EU vehicle kilometres, and scaling up of safety effects is based on EU accident numbers.

Finally the experience with the impact assessment and consequent updates and improvements of the methodology will be discussed.